Roll for rod mill and mounting arrangement therefor



May 26, 1970 w. L. KENNlcoTT 3,514,136

ROLL FOR HOD MILL AND MOUNTING ARRANGEMENT THEREFOR Filed Oct. 18, 1968United States Patent 3,514,136 ROLL FOR ROD MILL AND MOUNTINGARRANGEMENT THEREFOR Wilbur L. Kennicott, Ligonier, Pa., assignor toKennametal Inc., Latrobe, Pa., a corporation of Pennsyl- Vania FiledOct. 18, 1968, Ser. No. 768,843 Int. Cl. B60b 27/06 U.S. Cl. 287--53 11Claims ABSTRACT 0F THE DISCLOSURE A form roll of hard material, such ascemented tungsten carbide, for example, is mounted on a driving shaft. Adriving ring abuts one side of the roll and is keyed thereto byinteriitting lugs and notches on the roll and ring. A bar-like keyengages the notches in the shaft and ring and keys the ring to the shaftand is engaged by a screw which clamps the ring to the roll. A splitsleeve is forced between a cylindrical central bore in the roll and atapered portion on the shaft which the roll surrounds.

The present invention relates to the connection of forming rolls todrive shafts for the rolls and is particularly concerned with theapplication of the invention to rod mills and the like.

Rod mills and tube mills are well known and consist of a frame having aplurality of pairs of driven rolls through which the material beingtreated is passed for forming. The forming of the material isaccomplished by forming rolls having contoured grooves therein whichprogressively shape the member passing therethrough to the desired crosssectional configuration and size. A typical rod mill, for example, mighttake a round rod of a certain size and reduce it by progressive stagesto a round rod of a smaller size. Other cross sectional shapes are alsopossible.

The work load on such forming rolls is extremely heavy and in order toinsure an accurate end result and to eliminate slippage and breakage ofthe rolls and deiiection thereof, it is extremely important that theroll be firmly connected to its driving shaft. The extremely heavyservice to which the rolls are subjected requires that they be made of ahard material, such as cemented tungsten carbide. Heretofore, it hasbeen diicult and expensive to attach rolls of tungsten carbide to thesupporting shafts therefor and the present invention is particularlydirected to an improved mounting arrangement for rolls of this type.

Accordingly, the primary objective of the present invention is theprovision of an improved mounting arrangement for connecting formingrolls to the drive shafts in a rod mill or the like.

Another objective of this invention is the provision of a cementedtungsten carbide forming roll for a rod mill and a novel mountingarrangement therefor for xedly connecting the roll to its supporting anddriving shaft.

Other objectives and advantages of the present invention will `becomemore apparent upon reference to the following detailed specificationtaken in connection with the accompanying drawings in which:

FIG. l is a schematic representation of a rod mill;

FIG. 2 is a fragmentary sectional view indicated by line Il-Il on FIG. land showing more in detail the connection of a typical forming roll toits supporting and driving shaft; and

FIG. 3 is a perspective view showing the forming roll together with thering which keys the roll to the roll drive shaft.

In the present invention large, heavy shafts are provided 3,514,136Patented May 26, 1970 ICC firmly mounted in a supporting frame andarranged in pairs so that rolls mounted on the shafts will be presentedto each other to receive a work member such as a rod therebetween.

The rolls are mounted on a tapered portion of the shaft by a splittapered sleeve pressed into the space between the roll and the shaft andthe rolls are, furthermore, keyed to the shaft by a ring having notcheson one side to receive lugs on the forming roll and notches on the otherside to receive a bar extending through a hole or notch provided in thedrive shaft for this purpose. In this manner the rolls are firmly heldon the shaft against slipping thereon and are also supported againstdeection in any direction so that breakage of the rolls is minimized.

Referring now to the drawings somewhat more in detail, in FIG. 1 theframe of the rod mill is indicated at 10 and rotatably mounted thereinare shafts 12 arranged in opposed pairs and each carrying a forming roll14. A rod 16 of a larger size passes rightwardly through the rod milland emerges therefrom at the right and as a rod 18 of smaller size andpredetermined cross sectional configuration.

Turning now to FIG. 2 a typical shaft 12 is shown which is journaled inframe 10 as by a bearing 20 and, at the outside of the frame has a firstreduced diameter portion 22, a tapered portion 24, and a second reduceddiameter portion 26.

The first reduced diameter portion 22 receives a pair of rings 28 whichhave substantial annular cross sections thereof in abutting relation andwhich rings together confine a cavity 30 in which is a seal member 32,carried on a member 34 which is sealingly attached to frame 10 of therod mill.

Abutting the outer ring 28 is a forming roll 36 according to the presentinvention and abutting the outer side of roll 36 is a drive ring 38.

The roll 36 surrounds the tapered portion 24 of shaft 12 and positionedbetween the cylindrical central bore of roll 36 and the tapered portion24 of shaft 12 is the split tapered end region 40 of a sleeve member 42which extends outwardly a substantial distance beyond ring 38. At itsouter end sleeve 42 has an inwardly directed ange 44 and a retainer ring46 is connected to the end of sleeve 42 by screws `48 to define anannular cavity for receiving the radial flange 50 of a nut 52. Nut 52 isthreaded on a large bolt 54 having an exposed head 56, which at itsinner end, is threaded through a disc member 58 connected to the end ofshaft 12 by cap screws 60.

The second reduced diameter end portion 26 of shaft 12 has a transverseslot therein and closely receives a transversely extending bar-like key62. Key 62 is confined within the slot 64 provided therefor in the endof shaft 12 by disc 58 and, furthermore, has a conical recess 66 engagedby the conical end of screw 54. Key 62 extends through aperturesprovided therefor in sleeve 42 and engages notches 68 in the outer sideof ring 38. In this manner ring 38 is keyed to shaft 12 so as to rotatetherewith.

Ring 38 on its side facing roll 36 is also provided with radial notches70 into which extend the lugs 72 formed on the adjacent side of roll 36.The roll 36 is, thus, in turn, xedly keyed to shaft 12 to rotatetherewith while being firmly supported thereon by the split taperedportion 40 of sleeve 42.

The roll 36 is clamped tightly against rings 28 by turning screw 54 sothat key 62 is forced against ring 38 which in turn clamps roll tightlyagainst rings 28. thereafter, nut 52 is rotated to press sleeve 42toward roll 36 and this will press the tapered region 40 of the sleevefirmly into the space between roll 36 and tapered portion 24 of shaft12.

To permit the best bearing between the parts, lugs 72 on the roll 36 donot bottom in notches 70 of drive ring 38, and the bar-like key,similarly bottoms only in the notches 68 in drive ring 38.

After the foregoing adjustments have been made, lock nut 74 on screw S4can be tightened up against nut 52.

From the foregoing, it will be seen that the forming roll is extremelysolidly supported on its drive shaft and fixed thereon against rotationso that high work loads can be opposed on the roll Without the chance ofit slipping or its supporting shaft or becoming loose on the supportingshaft. The roll, furthermore, is also supported so that it has littletendency to break and thus can deliver the maximum useful life.

In connection with the strength of the roll, it will be evident that thesolid roll illustrated in this application has considerably greaterstrength than would be possible if the roll were made in sections as,for example, an outer roll part mounted on an arbor. The gain instrength of such a solid roll over a composite roll is calculated in themanner in which the strength of a beam is calculated. In the case of acomposite roll the strength would be calculated by the strength of thecubes of the radial thickness of the composite parts Whereas in the caseof a solid roll the strength is measured by the cube of the total radialthickness of the roll.

In the particular case where the roll is made of tungsten carbide, whichis a material having three times the resistance of defiection of steel,it will be evident that the solid carbide roll without a central arbordisposed between it and the shaft has much greater strength than acarbide roll of less radial thickness and having a steel sleeveinterposed between it and the support shaft.

Modifications can be made in the present invention falling within thescope of the appended claims.

What is claimed is:

1. In a mill, such as a rod mill having a frame, a shaft rotatable inthe frame with one end projecting from the frame and a roll mounted onthe projecting end of said shaft; said projecting end of said shafthaving a tapered portion in the axial plane of said roll and a shoulderbetween the tapered portion and the frame, said roll having acylindrical central bore larger in diameter than the largest diameter ofsaid tapered portion of said shaft, said roll on the side facing saidframe abutting said shoulder, a sleeve element having a region taperedon the inside and cylindrical on the outside, said region of said sleevebeing disposed in the bore in said roll and about the tapered portion onsaid shaft, a ring surrounding said sleeve and abutting said roll on theside thereof facing n away from said frame, first means keying said ringto said roll, second means keying said ring to said shaft, meansoperable for forcing said ring toward said roll to clamp the rollagainst said shoulder, and means operable for forcing said sleeveaxially on said shaft to wedge the said region thereof between said rolland said shaft.

2. An arrangement according to claim 1 in which said iirst meanscomprises interfitting lug and notches on the adjacent faces of saidroll and ring.

3. An arrangement according to claim 2 in which the lugs are on the rolland the notches are on the ring and the notches are deeper than theheight of the lugs so that the ring bears directly on the adjacent faceof the roll.

4. An arrangement according to claim 2 in which said second means keyingsaid ring to said shaft comprises laterally extending notches in saidshaft and in the side of the ring facing away from said roll, and abar-like key extending through the said notches.

5. An arrangement according to claim 4 in which the said notch in theshaft is in the outer end thereof, a retainer disc secured to the end ofthe shaft and confining the bar-like key in the notch in the end ofshaft, and said means for forcing the ring toward the roll comprising ascrew threaded through said retainer disc and engaging said bar-likekey.

6. An arrangement according to claim l5 in which said region of saidsleeve is split.

7. An arrangement according to claim 6 in which said means for forcingsaid sleeve element axially on said shaft comprises a nut threaded onsaid screw and rotatably engagng said sleeve.

8. An arrangement according to claim 7 in which said nut has aperipheral flange, said sleeve element having a recess in the outer endfor receiving said diange, and a retaining ring secured to the outer endof said flange and loosely confining the iiange on the nut in saidrecess.

9. An arrangement according to claim I8 in which said screw has a locknut threaded thereon for locking said nut with the flange to the screw.

10. An arrangement according to claim 1 in which the portion of saidsleeve element in said roll is radially thin and the roll from the outersurface of said sleeve element outwardly comprises a solid uninterruptedmass of metal.

11. An arrangement according to claim 10 in which said roll is formed ofcemented tungsten carbide.

References Cited I UNITED STATES PATENTS 1,166,408 12/1915 Blood 287-532,493,402 1/ 1950 Hahn 287-53 2,634,144 4/ 1953 Friedman 287-532,899,222 8/ 1959 Ross 287-53

